How to Harvest a Piezo Element From a Window Alarm

by friger

8.5K209

Intro: How to Harvest a Piezo Element From a Window Alarm

In this short instructable I will demonstrate how I harvest Piezo elements from dollar store window alarms.  Why you ask? Because these things are awesome pickups for guitars or any other acoustic instrument you are building. Also I am doing this to answer a question from a viewer of one of my instructables https://www.instructables.com/id/How-to-build-an-Electric-Guitar/. 

STEP 1: Take Things Apart

Open the battery compartment and remove the screw that holds everything together. Pull the back off. Pull the circuit board out and isolate the wires to the piezo.

STEP 2: Isolate the Part You Want.

In the movies they would be sweating over which wire to cut first, no such issue here, cut them both at the same time.

STEP 3: Remove the Part You Want.

OK, this is the only tricky bit, cutting the plastic housing to get the element out without bending it. A little bend won't hurt anything but you don't want to crack that white disc in the middle.

9 Comments

fcharest1 10 years ago

anyone knows how to make sound with this ? when I plug it to 4.5V no noise is made ?

Honhenheim 11 years ago

Dollar stores are your friend, cheap made stuff, with some good insides. Screws, wires, speakers, etc. You can even get solar panels and a rechargable battery from those yard lights. Thank you for this instructable, might come in handy in the future.

tmuck 12 years ago

Friger, you're still my hero. and by the way, i've started designing my electric uke. or (electruke). I can't wait to get to work on building it. :D

friger 12 years ago

I love the name, quick, patent it.

mnmc10 12 years ago

this thing will make a noise when the magnet is removed but will turn off once the magnet is put back. you guys have an idea to prolong the sound for a few seconds even if you put back the magnet back? kinda like a delay?

arnefl 12 years ago

And the leftover can be used for lots of things. I have one for a fridge/freezer reminder. I soldered a LED where the piezo used to be and it blinks if either freezer door or refrigerator door is open

friger 12 years ago

I've never thought of that, great idea.

Bongmaster 12 years ago

normally they have a hal effect sensor too, unless they cheapskate

Bongmaster 12 years ago

im guessing the long folded metal pins overlapping each other are the reed switch, so cheap they didnt even bother with a real one O_o